Demonstration of Self-Updating Landslide Hazard Maps with Dynamic Crowd-Sourced Data in Rwanda

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Digital Rights Management: Improving Online Digital Images Copy Rights Management through an Enhanced Least Significant Bit Steganographic Algorithm

Digital media no doubt presents numerous advantages compared to the traditional analog media. Of the most importance is the fact that digital content (images, graphics, audio and video) can be easily copied, transmitted, retrieved and distributed over private and open access networks. The global availability of the internet- certainly the most impactful information exchange tool today- plus the numerous file sharing tools freely available have made the distribution of copyrighted digital media files simple and straightforward. Duplication of exact copies of original images, for example can be easily done and circulated without authentication. As much as this is an advantage in trying to enhance sharing of information, it certainly creates problems of ownership and authenticity and digital rights protection. There already exists copyright laws that provide for protection of all online content but the task of continuously guarding the web and correctly identifying those that infringe against these laws is increasingly becoming enormous. There is therefore need to continuously invest in development of new technologies and algorithms that will make it more and more difficult to illegally copy or use someone else content. To improve security of copyrighted online digital images, this paper proposes the use of an enhanced LSB steganographic algorithm that employs a selective and randomized approach in picking specific number of target image bits to swap with the owners signature authentication bits using a pseudo random number generator (PRNG). The carefully selected password seed is used to determine the set of selected numbers used for targeting specific image bits for the signature hiding. An experimental design is setup to determine the effectiveness of the method by comparing and analyzing the stego images’ statistical characteristics and the ability of steganalysis methods to detect the hidden signature. The experimental results indicate improved levels of imperceptibility and hence improved security against illegal copying. Keywords: Digital Media, Steganography, Copyright, Steganalysis, Stego image, imperceptibilit

Economic Evaluation of Organic and Inorganic Resources for Recapitalizing Soil Fertility in Smallholder Maize-based Cropping Systems of Central Kenya

Structural adjustments programs (SAPs) in the last two decades have eliminated all farm-support programs leading to low usage of fertilizers by Kenyan smallholders. One way of addressing this problem is use of organic nutrient resources. This paper examines their cost-effectiveness as capital investments in replenishment of Nitrogen (N), Phosphorus (P), Potassium (K) and soil organic matter (SOM) in smallholder, Maize-based cropping systems. On-farm trials were established in Maragwa and Kirinyaga Districts in 2003/04. Maize was planted in 3 replicates in randomised complete block design (RCBD) using different levels of organic and inorganic fertilizer resources. A blanket rate of 40kg P/ha was applied in all treatment except the control to increase organic N-utilization efficiency. The test crop was harvested, oven-dried and weighed. Net Present Values (NPV) were computed using Partial Budgeting Analysis Model. Increasing levels of inorganic N increased maize yields significantly (P<0.05). However, higher yields were necessary but not sufficient criteria to determine profitability of different treatments. Manure + 60 kg N/ha gave highest NPV (USD 564), Manure + 40kg N/ha gave second highest NPV (USD 511) in Maragwa District while Manure + 60kg N/ha gave highest NPV (USD 633) and Manure + 40kg N/ha second highest NPV (USD 618) in Kirinyaga District. These results suggested that higher N-levels were not necessarily the most economical. Use of organic resources with modest amounts of mineral fertilizers seemed more profitable and held the key to enhancement of nutrient budgets, food security and rural livelihoods.Natural resource capital, Net present values (NPV), Nutrient budgets, Smallholder farmers, Soil organic matter (SOM), Structural adjustment programs (SAPs), Crop Production/Industries, Land Economics/Use,

Interaction between financial risk management and value of the firm among private equity firms in frontier markets : a theoretical perspective

Purpose: The study attempts to establish a theoretical basis for the interaction between financial risk management and value of the firm among private capital firms. Design and Methodology: The study was based on a theoretical review of the interaction between financial risk management and value of the firm focusing on the applicability of agency theory, trade-off theory and credit metrics model in anchoring capital management risk, liquidity risk and credit risk Findings: The study shows that although private equity firms are not publicly listed, they face financial risks associated with defaults on loans advanced, volatility of interest rates, liquidity management and capital management. The agency theory explains the role of capital management risk and liquidity risk by incurring agency costs to deter the management from engaging in activities hindering achievement of wealth maximization goal. Similarly, companies balance between threat of bankruptcy and tax benefits of debt by finding an understanding between the advantages and the disadvantages that come with debt as outlined in the trade-off theory while credit metrics model help firms to quantify credit risk on loans, fixed income instruments, commercial contracts. Practical Implications: Private equity firms must constantly be engaged in risk mitigation activities by extensively evaluating their financial, legal and business environments. The management of private equity companies must also always try to balance between the threat of bankruptcy and the tax benefits of debt in the formulation of capital structure by finding a compromise between the benefits and costs of raising debt. The management should also carefully consider credit risks during the credit appraisal and credit awarding process by using appropriate credit appraisal models such as credit metrics model. The Significance of the Study: The conclusions reached in this study significantly impacts the perspective of the management with regard to risk management particularly in the banking sector which is predominantly adversely affected by credit risk, liquidity risk and capital management risks. Consequently the management would be in a better position to manage their risks using appropriate models and improve organizational efficiency and performance.peer-reviewe

Determining the Economic Value of Irrigation Water in Kerio Valley Basin (Kenya) by Residual Value Method

This paper presents an application of the residual value technique to determine the disaggregated economic value of irrigation water used across crops at the basin level for the Kerio valley basin Kenya. A multistage sampling method was used to select a representative sample of 216 smallholder irrigation farmers. Data was collected using a structured questionnaire administered to the small holder farmers, additional data on irrigation water requirements was obtained from FAO, CROPWAT 8.0 and CLIMWAT 2.0 (2013) database. The average residual value in the basin is Ksh 6.17 per M3. Results for the economic values of irrigation water are Ksh/ M3 20.85, 14.87, 4.3, 11.28, 1.25, 0.3 for field food crops; green grams, maize, millet, sorghum, cassava and cowpeas are respectively. Similarly for the fruit trees bananas, mangoes and lemons, the economic value of irrigation water are Ksh/M3 1.36, 0.90, 0.45 respectively Green grams and maize had the highest values for the ratios of apparent productivity and residual value and cowpeas and lemons the lowest. The results shows that at crop level water values estimated for field crops are generally higher compared to fruit trees. This means that there is greater potential in field crops than fruit trees in the basin. Keywords: Irrigated agriculture, apparent productivity, value of water, residual value metho

APPLICATION OF KALMAN FILTER TO ARTIFICIAL NEURAL NETWORKS PREDICTION FOR FOREIGN EXCHANGE RATES

In recent years, artificial neural networks have received increasing attention as a decision making tool when prediction of financial time series is concerned. Modeling issues associated with artificial neural network model like the size of sample data and the general architecture of the model affect the performance of the model. For this reason, artificial neural networks outputs are prone to over-fitting or under-learning resulting to large mean squared errors which affect the accuracy of the prediction. In this paper, we investigate if the application Kalman filter algorithm to artificial neural networks model output can improve the model accuracy through the reduction of the mean squared error. Performance measures for prediction accuracy were used to compare the two models over the datasets for dollar, Euro and Pound exchange rates in Kenya Shilling for a period of five years. In the entire cases artificial neural networks model performed better than artificial neural networks with Kalman filter model. Keywords: Artificial Neural Networks, Currency, Exchange Rates, Kalman Filter, Multi-Layer Perceptro

The effect of alpha(+)-thalassaemia on the incidence of malaria and other diseases in children living on the coast of Kenya

BACKGROUND: The alpha-thalassaemias are the commonest genetic disorders of humans. It is generally believed that this high frequency reflects selection through a survival advantage against death from malaria; nevertheless, the epidemiological description of the relationships between alpha-thalassaemia, malaria, and other common causes of child mortality remains incomplete. METHODS AND FINDINGS: We studied the alpha+-thalassaemia-specific incidence of malaria and other common childhood diseases in two cohorts of children living on the coast of Kenya. We found no associations between alpha+-thalassaemia and the prevalence of symptomless Plasmodium falciparum parasitaemia, the incidence of uncomplicated P. falciparum disease, or parasite densities during mild or severe malaria episodes. However, we found significant negative associations between alpha+-thalassaemia and the incidence rates of severe malaria and severe anaemia (haemoglobin concentration &lt; 50 g/l). The strongest associations were for severe malaria anaemia (&gt; 10,000 P. falciparum parasites/mul) and severe nonmalaria anaemia; the incidence rate ratios and 95% confidence intervals (CIs) for alpha+-thalassaemia heterozygotes and homozygotes combined compared to normal children were, for severe malaria anaemia, 0.33 (95% CI, 0.15,0.73; p = 0.006), and for severe nonmalaria anaemia, 0.26 (95% CI, 0.09,0.77; p = 0.015). CONCLUSIONS: Our observations suggest, first that selection for alpha+-thalassaemia might be mediated by a specific effect against severe anaemia, an observation that may lead to fresh insights into the aetiology of this important condition. Second, although alpha+-thalassaemia is strongly protective against severe and fatal malaria, its effects are not detectable at the level of any other malaria outcome; this result provides a cautionary example for studies aimed at testing malaria interventions or identifying new malaria-protective genes

RANDOMISED DOUBLE BLIND STUDY TO COMPARE EFFECTIVENESS OF HONEY, SALBUTAMOL AND PLACEBO IN TREATMENT OF COUGH IN CHILDREN WITH COMMON COLD

Background: Acute upper respiratory infection is the most common childhood illness and presents with cough, coryza and fever. Available evidence suggests that cough medicines may be no more effective than honey-based cough remedies. Objective: To compare effectiveness of honey, salbutamol and placebo in the treatment of cough in children with acute onset cough. Design: Randomised control trial Setting: Aga Khan University Hospital Paediatric Casualty Subjects: Children between ages one to twelve years presenting with a common cold between December 2010 and February 2012 were enrolled. Outcome measures: Frequency, severity and extent to which cough bothered and disturbed child and parental sleep were assessed at baseline and over the subsequent five days through telephone interview using a validated scoring tool. Results: One hundred and forty five children were enrolled in the study (45- placebo, 57 –honey, 43 –salbutamol). Of the 145 children 51% were male. Honey significantly reduced the total mean symptom score by day three (p\u3c 0.001). Total mean difference in scores between day zero to five demonstrated a significant difference of honey’s efficacy over placebo (p\u3c 0.002) however no difference was noted when compared to salbutamol (p\u3c0.478). Significant differences in both total as well as each individual symptom score was detected with honey consistently scoring the best whilst placebo and salbutamol scored the worst. In paired comparisons honey was superior to placebo but not salbutamol, whilst salbutamol was not superior to placebo. Conclusion: Honey was most effective in symptomatic relief of symptoms associated with the common cold whilst salbutamol or placebo offered no benefit

Using farmer-prioritized vertisol management options for enhanced green gram and tomato production in central Kenya

Green gram (Phaseolus aures L.) and tomato (Solanum lycopersicum L) are widely grown in the vertisols of the Mwea Irrigation Scheme in Kenya alongside the rice fields. Green gram can fix nitrogen and is grown for its highly nutritious and curative seeds while tomato is grown for its fruit rich in fiber, minerals and vitamins. The two can be prepared individually or together in a variety of ways including raw salads and/or cooked/fried. They together form significant delicacies consumed with rice, which is the major cash crop grown in the black cotton soils. The crops can grow well in warm conditions but tomato is fairly adaptable except under excessive humidity and temperatures that reduce yields. Socio-economic prioritization by the farming community and on-farm demonstrations of soil management options were instituted to demonstrate enhanced green gram and tomato production in vertisol soils of lower parts of Kirinyaga County (Mwea East and Mwea West districts). Drainage management was recognized by the farming community as the best option although a reduced number of farmers used drainage and furrows/ridges, manure, fertilizer and shifting options in that descending order. Non-availability of labour and/or financial cost for instituting these management options were indicated as major hindrances to adoption of the yield enhancing options. Labour force was contributed to mainly by the family alongside hiring (64.2%) although 28% and 5.2%, respectively used hired or family labour alone. The female role in farming activities dominated while the male role was minimal especially at weeding. The youth role was insignificant and altogether absent at marketing. Despite the need for labour at earlier activities (especially when soil management options needed to be instituted) it was at the marketing stage that this force was directed. Soils were considered infertile by 60% but 40% indicated that their farms had adequate fertility. Analysis showed that with ridging, farm yard manure and fertilizer improved soil fertility, crop growth and income considerably. Phosphate and zinc enhancement reduced alkalinity and sodicity. Green gram and tomato yields increased under ridges and farm yard manure application by between 17-25% which significantly enhanced household incomes.Key words: Green gram, Tomato, Vertisol management, Household income, Mwea, Keny

Severe road traffic injuries in Kenya, quality of care and access

Background: Road traffic injuries (RTI) are on increase in developing countries. Health care facilities are poorly equipped to provide the needed services. Objective: Determine access and quality of care for RTI casualties in Kenya. Design: Cross-sectional survey Setting: 53 large and medium size private, faith-based and public hospitals. Participants: In-patient road traffic crash casualties and health personnel in the selected hospitals were interviewed on availability of emergency care and resources. Onsite verification of status was undertaken. Results: Out of 310 RTI casualties interviewed, 72.3%, 15.6% and 12.2% were in public, faith-based and private hospitals, respectively. Peak age of the injured was 15-49 years. First aid was availed to 16.0% of casualties. Unknown persons transported 76.5% of the injured. Police and ambulance vehicles transported 6.1% and 1.4%, respectively. 51.9% reached health facilities within 30 minutes of crash and medical care provided to 66.2% within one hour. 40.8% of recipient facilities were adequately prepared for RTI emergencies. Conclusions: Most RTI casualties were young and from poor backgrounds. Training of motorists and general public in first aid should be considered in RTI control initiatives. Availability of basic trauma care medical supplies in public health facilities was highly deficient